Help requested - QW 757 night textures

Hi everyone - I have night textures on my QW 757 repaints working properly on every area of the aircraft except the landing lights.  

Regardless of applying the night landing lights to my textures and placing the correct file in the livery texture folder, I still just get a washed-out flood of light over the daylight textures.  I have used this correct procedure to the vertical stabiliser, windows, winglets, etc. and those all work properly with richly coloured and nicely lit results (much better than the default QW textures incidentally).

If anyone knows how to resolve the landing lights textures properly I would be grateful for your help.

Cheers.